It's all about expectations. Looking at the expectations that Capcom, Nintendo, retailers and gamers had for this game, and looking at the sales of the first 2 weeks, than all i can say is this: The sales of Monster Hunter 3 did not meet expectations, FOR NOW.
I mean, the last 2 Monster Hunter games sold 892.000 and 1.439.000 copies in 2 weeks time. With that knowledge the 700.000 copies sold of Monster Hunter 3 doesn't sound like a lot. And yes, it's already the best-selling third party game in Japan, on current-gen consoles, and it will probably reach 1 million copies. BUT, if Final Fantasy XIII on the PS3 would sell 700.000 copies in 2 weeks than everybody would call it a bomb. Why? Because sales of previous Final Fantasy games give higher expectations.
I'm not saying Monter Hunter 3 bombed, it's too early to tell, but it's sales sure didn't meet my expectations. And looking at the current MH3 price at certain Japanese retailers i think we all can agree that MH3 sales of the first two weeks didn't meet their(retailers) expectations as well.